At present, communication within a motor vehicle between different motor vehicle components, such as a door controller and a seat controller, takes place, among other things, using a bus system operating, for example, according to the CAN (Controller Area Network) standard, or according to the LIN (Local Interconnect Network) standard.
Prior patent applications of the applicant discuss, for a motor vehicle electrical system, which is basically used for supplying power to motor vehicle components, and which is also used for transmitting data between the components (compare German patent applications nos. 101 42 408 and 101 42 410, both filed on Aug. 31, 2001). This communication method via the motor vehicle electrical system for power supply is also referred to as “powerline communications”.
Communication between the components via existing bus systems and/or over powerline communications requires powerful and interference-resistant transmitter/receiver devices (so-called “transceivers”) that guarantee reliable communication even under difficult conditions. A transceiver implements the access of a component to a communications network.
Interferences that may affect data transmission can be caused by line-conducted impulse noise, but also by impulse noise that radiates interference pulses into the vehicle electrical system. Line-conducted impulse noise can be caused, for example, by switching operations of electrical loads, or by ignition processes. These are, in particular, all kinds of switching operations of an on-board electrical load connected to the vehicle electrical system, such as the seat adjuster, horn, lighting, etc. Interfering ignition processes occur, in particular, in the case of a high-voltage ignition system as is used, for example, in Otto engines.
In particular, the transceivers must also be able to transmit, without delay, messages of safety-related applications, such as air-bag triggering, or brake interventions of a vehicle stability control system.